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Oh, that's odd. It is indeed a Toshiba. I skipped that bit.

The ones in arcade cabs are Hitachi A68KSA30X.

They're different tubes.
 
The picture of the 1st tube looks like a bonded yoke to me. To echo nem, its highly unlikely that a consumer tv yoke would measure out to meet ms9 spec or ms2931 spec yokes.

Consumer TVs (and their yokes) almost never were designed to drive 24Khz or 31Khz signals, thus are likely incompatible from electrical standpoint with those chassis.

This means you need the original yoke from the arcade monitor to swap onto the donor tube. In your case, if the tube fits the blast bezel, then you just need to find a ms2930/31/33 yoke to swap that arcade monitor yoke with the consumer tv yoke.

FWIW, 19" or A48xxx tubes usually can retain their yokes for the purpose of installing an arcade monitor chassis. Many 19" arcade chassis's (K7000s for instance) are typically made for low impedance 15Khz yokes and most 19" consumer tv yokes (from the mid 1990s onward at least) are within a similar spec and thus can be compatible without a yoke swap. I have never sourced a 27" or A68xxx tube from a consumer TV that is compatible with any dual res or tri-sync montior without a yoke swap.
So to clarify,
Can I tube swap this bonded yoke tube using an ms29 yoke? And make it work?
If I can remove the bonded yoke???
Obviously adding purity rings to it etc.
Or not possible to use a bonded yoke??
 
Also, does anyone have a set of purity rings and a ms2931 yoke they can spare?? I'd like to try to make this work for my badly burned Blast tubes. But I won't be mad if I can use this for an awesome ms9 chassis either 😉
 
Also, does anyone have a set of purity rings and a ms2931 yoke they can spare?? I'd like to try to make this work for my badly burned Blast tubes. But I won't be mad if I can use this for an awesome ms9 chassis either 😉
Always best to use the rings from the TV set you sac'ed the tube from. The yoke on the other hand is another story.
 
So to clarify,
Can I tube swap this bonded yoke tube using an ms29 yoke? And make it work?
If I can remove the bonded yoke???
Obviously adding purity rings to it etc.
Or not possible to use a bonded yoke??
If it has a bonded yoke don't bother. It'll be a lot of work to remove it and it's a crapshoot as to whether you'll get a decent picture.

I have had zero luck with tubes using bonded yokes, almost always have purity issues.
 
So to clarify,
Can I tube swap this bonded yoke tube using an ms29 yoke? And make it work?
If I can remove the bonded yoke???
Obviously adding purity rings to it etc.
Or not possible to use a bonded yoke??
Bonded yoke will be a pain to remove and you would need to source convergence rings that fit the tube from the tv. No guarantee of the success of that.

An easier prospect would be to find another chassis compatible with the tv yoke and swap that into the blast instead of the ms2931. I am not recommending that path but it would be easier to get that suitable than trying to remove bonded yoke.

Highly unlikely that bonded yoke is compatible with a nanao, but perhaps a wells Gardner k7400 or u2000 or u5000. Obviously this would require reterminating the jst and amp up connections to the spec needed for the wg chassis. It’s work either way
 
I'm hesitant to mess with the bonded yoke now after hearing no success stories and idk how I'd source the correct purity rings for it so I'll leave it be as a retro gaming TV for someone to enjoy. (Pics of snes composite) nice thick scan lines)
I will proceed with the 1st Toshiba tube and will try both an ms9 and ms2931 to see which one works best.
 

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Any luck finding that TV model? This Toshiba A68KSA30X tube has really got me curious.
Here you go.
The fly back looks similar but not a perfect match. Numbers are different as well. I wonder if a flyback from this TV would work on an ms9 or ms29...
 

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I tried an ms9 with the regular yoke I got a really faint/short horizontally image. Took off the stock TV yoke threw on an ms9 yoke and rings and got no image at all. Kinda bummed
Should I try the TV purity rings and ms9 yoke next?
 
This A68KSA30X12 tube looks like a perfect match physically to the A68KZN699X in the blast. I got spare and yoke and MS-2930 coming my way to try my hand at a swap.

Never gone as far as swapping the yoke on any CRT so thoughts and advice would be appreciated. Might be able to get a second tube.

PXL_20221217_175127425.jpg
 
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This A68KSA30X12 tube looks like a perfect match physically to the A68KZN699X in the blast. I got spare and yoke and MS-2930 coming my way to try my hand at a swap.

Never gone as far as swapping the yoke on any CRT so thoughts and advice would be appreciated. Might be able to get a second tube.

PXL_20221217_175127425.jpg
It's a matter of trial and error when yoke swapping. Unscrew the consumer yoke and rings and they should just slide right off. Sometimes they're glued in place with some silicon, so you'll have to cut the glue to loosen it.

Slide the nanao yoke in place and reuse the consumer television convergence rings. Connect the yoke wires to your nanao chassis and turn it on to see if you get an image. If you get any picture that's a good sign. Chances are you'll need to adjust the yoke on the neck to correct any purity issues by sliding it back and forth until you hit the sweet spot. You might also need to adjust the convergence rings to correct purity issues as well, which can be a giant pain in the ass.

You can watch delusional arcades video on how he tube swapped a k-7000 to get a better idea.

View: https://www.youtube.com/watch?v=JjznOc5SHEY
 
It's a matter of trial and error when yoke swapping. Unscrew the consumer yoke and rings and they should just slide right off. Sometimes they're glued in place with some silicon, so you'll have to cut the glue to loosen it.

Slide the nanao yoke in place and reuse the consumer television convergence rings. Connect the yoke wires to your nanao chassis and turn it on to see if you get an image. If you get any picture that's a good sign. Chances are you'll need to adjust the yoke on the neck to correct any purity issues by sliding it back and forth until you hit the sweet spot. You might also need to adjust the convergence rings to correct purity issues as well, which can be a giant pain in the ass.

You can watch delusional arcades video on how he tube swapped a k-7000 to get a better idea.

View: https://www.youtube.com/watch?v=JjznOc5SHEY
Thank you, I will watch the video and see what I can figure. I wouldn't have guessed that I would reuse the rings on the tube already but that does make sense now that I think about it.

Do you typically get better results by using the same brand tubes with similar model numbers?

I was shooting for as close to the same year and brand with the idea that Toshiba would have similar specs for tooling for manufacturing tubes worldwide.
 
If it has a bonded yoke don't bother. It'll be a lot of work to remove it and it's a crapshoot as to whether you'll get a decent picture.

I have had zero luck with tubes using bonded yokes, almost always have purity issues.

The service manual says this is a bonded yoke and the sixth symbol in the Toshiba type number suggests its bonded but the neck has sets of rings on it. Is this similar to the other bonded yokes you have tried?
 

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It does look like it has some adhesive where the clamp is. Loosen the clamp and try to twist the yoke, see what happens.
 
It does look like it has some adhesive where the clamp is. Loosen the clamp and try to twist the yoke, see what happens.

I guess it being bonded was incorrect, it came off with minimal effort.

Edit: added a couple pictures with the tube out and the blast bezel laying on top of it. This tube has a bit more of a curve than the A68KZN699X but it is the right size not horrible.
 

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